Dungeness nuclear power station in Kent. The Conservatives are in favour of building new nuclear reactors, while the Liberal Democrats are against. Photograph: Dan Kitwood/Getty Images

Nuclear power

This is a major point of disagreement between the two parties. The Conservatives are in favour of building new nuclear reactors, and the Liberal Democrats are against.

Simon Hughes, previously the Liberal Democrats' energy spokesman, has said: "A new generation of nuclear power stations will be a colossal mistake, regardless of where they are built. They are hugely expensive, dangerous and will take too long to build." The Lib Dem leader Nick Clegg reiterated a similar line in the leaders' debates.

In a statement today, the coalition said: "We have agreed a process that will allow Liberal Democrats to maintain their opposition to nuclear power while permitting the government to bring forward the national planning statement for ratification by parliament so that new nuclear construction becomes possible." Under this arrangement, we will have the odd experience of a Liberal Democrat speaking against his or her own government's planning statement for nuclear power. Lib Dem MPs will then abstain.

Martyn Williams, Friends of the Earth's (FoE) senior parliamentary campaigner, said the high cost made a new fleet of nuclear power stations unlikely. "The Conservatives I've spoken to are clear no public money will go into nuclear, and have even discussed whether that promise should be set down in law. And because the Liberal Democrats will abstain on nuclear, the Conservatives will be a minority government on nuclear."

Global climate talks

Both parties are committed to pursuing a global deal to cut greenhouse gas emissions. But their differing enthusiasm for Europe, particularly the Eurosceptic MPs to the right of the Conservative party (not least Hague), may cause rifts over whether to back European negotiating positions.

Carbon cuts

The Liberal Democrats have proposed a 40% cut in carbon emissions by 2020, going deeper than the 34% advised by the government's independent advisory body under the Climate Change Act of 2008. The Tories support the 34% target though they did not explicitly mention it in their manifesto. It's not yet clear whether the new government will settle on a higher figure, such as the 42% cut recommended by campaigners.

Alex Randall, a spokeman for the Centre for Alternative Technology (CAT) said the Liberal Democrats had been more aggressive in their plans for cutting carbon emissions and that it would be significant if a Lib Dem was appointed as minister for energy and climate change.

Aviation and transport

Both parties oppose Heathrow expansion and agree on the need to develop high-speed rail. Plans for a third runway at Heathrow will be formally shelved. Williams said there was still a question mark over whether the new government would allow or oppose expansion at other airports. The Lib Dems oppose such expansion but the Tories left the door open to more airport capacity. Both today ruled out additional runways at Gatwick and Stansted.

The new government is also backing a Lib Dem policy of replacing air passenger duty with a per flight duty, which means empty planes are taxed as highly as full ones.

Both parties are keen on electric cars and today announced they will develop a national charging network. The Liberal Democrats also proposed swapping vehicle excise duty for a road pricing scheme, though Williams said this now looks unlikely to be a policy adopted by the new government.

Conservation

The Tories have proposed "conservation credits", a scheme under which developers must pay for damage done to the environment that funds for improvements elsewhere. The Lib Dems have called for a new status for "locally important" areas. It is not clear yet which, if either of these policies, will be prioritised.

Today's agreement between the parties does promise "measures to promote green spaces and wildlife corridors in order to halt the loss of habitats and restore biodiversity."

Renewable energy

Both parties back more investment in "clean energy". The Conservatives have been very clear that they will not back specific low-carbon technologies, but will leave the market to decide. Greg Clark, formerly the shadow climate secretary, wrote recently on environmenttheguardian.com: "Having set the right incentives, government then needs to realise that it is the creative interactions of millions of investors, producers and consumers that will truly create the low-carbon economy."

The CAT's Randall said the two parties had distinctly different priorities on low-carbon technologies. "The Conservatives have always favoured a combination of high-tech plus microgeneration - nuclear and carbon capture and storage, plus lots of domestic generation. The Lib Dems have favoured an approach using existing technologies, such as rolling out onshore and offshore wind to a much greater extent, as well as reducing energy demand. It will be interesting to see which approach wins out."

10:10 climate campaign

The new government today appeared to have signed up to the principle of the 10:10 climate campaign, which calls for individuals and organisations to cut carbon emissions by 10% in 2010. In a statement, it promised a "commitment to reduce central government carbon emissions by 10% within 12 months." Both the Tories and the Lib Dems last year called for the government to sign up to the campaign, but it was defeated by Labour.

Green investment bank

Like Labour, both the parties support the idea of a green investment bank to finance new low-carbon energy developments. Today's coalition agreement confirms the bank will go ahead, but the key unknown is where the financing will come from. When former chancellor Alistair Darling announced plans for such a bank in the last budget, he said it would have £2bn funding, with £1bn from the government through the sale of the Channel Tunnel and the other £1bn from the private sector. The Lib Dems had promised a £3.1bn green economic stimulus in their manifesto, but it remains to be seen how much money the coalition will put into a green bank and how much slack private investors will pick up.

Green homes

Both sides of the coalition have proposed grants and schemes to help householders green their homes. Today's coalition agreement green lights a "pay as you save" green loan scheme which Labour announced earlier this year and continuing the feed-in tariff for microgenerators of green electricity, which launched in April. The Lib Dems also support the feed-in tariff and in their manifesto proposed a £400 cashback for double glazing, efficient boilers and solar panels.

"Will these things feature in first Queen's speech?" Williams asked. "It's a question of whether the coalition prioritise energy and climate. Most of the ministers I've spoken to have been on the environment side and they say it will be, though that doesn't yet prove it will be. Cameron, for example, didn't mention environment in his speech outside of Downing Street last night." Both the new PM and his deputy, however, mentioned the environment in their first press conference today. Clegg said this is a government where "fine words on the environment are finally translated into real action" and Cameron said it was "passionate about building a green economy."